The invention relates to a lightning protection system for a radome as well as a method for assembling the lightning protection system on a radome.
The invention is particularly advantageously applicable to aircraft radomes.
Lightning may cause significant damage to aircraft during flight. In order to protect aircraft and minimize the damage that may be caused by lightning, it is known to place strips protecting against lightning on the radome of the aircraft.
A first known system for protecting against lightning is made up of metal strips positioned on the outer face of the radome. FIG. 1 illustrates this device. In order to minimize aerodynamism problems, the metal strips b are positioned radially on the outer face of the radome, starting from the periphery of the radome and targeting the tip P thereof. The metal strips are electrically connected to the ground of the aircraft. When lightning strikes the radome, the metal strips b guide the lightning to the ground of the aircraft.
In order to eliminate the aerodynamism problem, a system is known from the prior art in which the metal strips are positioned inside the radome, and the metal strips are attached on the radome using metal studs that are flush with the outer wall of the radome. Such a system is described in the French patent application filed by the Applicant dated Dec. 11, 2007, under no. 07 59733 and entitled “Système parafoudre et aéronef comportant un tel système.” Out of a concern for symmetry and connection of the metal strips to the fuselage of the aircraft, the latter are positioned radially on the inner face of the radome. FIG. 2 illustrates the connection between a metal stud 1 that is flush with the outer wall of the radome and a lightning protection strip b situated on the inner face of the radome. The metal stud 1 is fastened in the wall of the radome R using a spacer EN, and the metal strip b is screwed to the metal stud 1. The lightning F that strikes the metal stud 1 on the side of the outer wall 2 of the radome is then guided to the strip b situated on the side of the inner wall 3 of the radome.
Although this second device makes it possible to resolve the aerodynamism problem, the position of the metal strips continues to disrupt the radiation emitted by the antenna. In fact, due to the presence of the metal strips b positioned radially on the inner face of the radome, the total energy emitted in the far range is lower than the total energy that would be emitted without strips. Likewise, the radiation pattern is also disrupted relative to the pattern that would be obtained without strips.
The invention does not have the aforementioned drawbacks.